Cancers, having increased incidence rate in the last decade of the 20th century, require substantial effort from medical professionals in terms of early diagnosis, logistics and availability of suitable treatment. However, it is appreciated that over 1.3 million new (skin) cancers are diagnosed annually and are increasing at a rate of about 5% per year.
Non proliferated cancers, being substantially superficial lesions, may be treated in different ways. First, surgery may be envisaged. However, such technique may be disadvantageous in terms of long waiting lists and complications related to post-treatment care. In addition, due to invasive character of surgery contamination of the wound by infections may present an additional risk. Secondly, external irradiation using electrons or electromagnetic radiation may be envisaged. Such techniques have a disadvantage that the patient has to receive about 25-30 fractions, which may be complicated for less mobile patients. In addition, irradiation of healthy tissues as well as reproducibility of the external beams with respect to the movable target may be a challenge.
Brachytherapy may provide an attractive compromise, wherein the radioactive sources are delivered inside the patient using applicators, either interstitially or intracavitary. Usually, a medical professional employs a standard applicator for treating different patients. However, due to difference in local anatomies the standard applicator may be not always an optimal solution for matching the patient geometry and for providing a pre-planned dose distribution inside the patient. Embodiments of the standard applicators are known from Nucletron, Applicator guide, Company Brochure, 2011.
Recently, it has been attempted to provide a customizable applicator, which may be composed of modules. An embodiment of a modular applicator is known from US 2011/0257459. In the known modular applicator a stack of longitudinal segments is provided, wherein the segments may be coupled to each other using suitable cooperating surfaces. Each segment is provided with a plurality of passages for providing a set of customizable channels for insertion of a radioactive source. A tip of the stack of segments may comprise one or more alignment notches, which may help define a certain orientation between the tip and a distal stacking component.
It is a disadvantage of the known modular applicator that it insufficiently provides the orientational certainty to the handling medical specialist. In particular, the stack of the segments having a number of pre-selected paths for the radioactive source may accidentally rotate about the central axis, which may lead to errors in dose delivery.